1.5" MDF, approx 2.8 cu. ft. I would be using it in the home with possibly a Peerless 10" SLS; might cover it (it's carpeted) with some very thin MDF & then veneer, add amp, spikes, grill etc.

I listen to jazz & classical and not to extremes, & since I live in a condo I prefer not to build boxes, and if I can get one that needs no extra internal reinforcement that's even better. Yeah it's really heavy but they're shipped from LA and I live in San Diego, so I can handle the UPS.

I've tried removing carpet from these things before - lots of huffing & puffing and a very rough layer of glue underneath that takes a lot more huffing and puffing to sand (I try to avoid using machines due to the neighbors).

I suppose I could try a release agent, but it's so easy to just cut a layer of board, lay on a good coat of glue, and use the box's own weight (especially in this case) plus other heavy stuff I have lying around, to clamp the wood down. Works pretty well, especially with some small finishing nails for good measure.

Bracing can have various effects which may be good or not so good for a particular use. As this appears to be a sub, I feel there is the opportunity to push the resonances up beyond the sub's passband where they don't matter as much, so yes, I would brace. I have used 1.5" MDF and it does resonate.

Originally posted by lndm Bracing can have various effects which may be good or not so good for a particular use. As this appears to be a sub, I feel there is the opportunity to push the resonances up beyond the sub's passband where they don't matter as much, so yes, I would brace. I have used 1.5" MDF and it does resonate.

Thanks Indm - this makes me think of the next logical question then - how does one best add bracing to a pre-built sub box? Or should it even be attempted? Certainly you could separate one of the panels with a saw I suppose, but then we're getting into as much labor as it would probably take to build from scratch, which is what I'd rather avoid.

Modern thinking tends to advocate the shelf brace, YMMV. It would be possible to insert braces that are the size of the front baffle (internal). You may need to cut them in half to get them through the woofer hole, then overlap the halves inside. You might want to glue cleats into the box first.

The simplest bracing though, if you want the least effort, is to glue ribs along the existing panels (this could even be done on the outside of the box).

Hey Relax - thanks for the more accurate volume calc - mine was very off the top of my head. Actually looks better for my goals.

INDM - the rib method looks like the simplest way to go, and the external application is intriguing - you could cover the entire exterior with ribs and then add another set of panels over that, to make a VERY dense and rigid structure - like a box within a box.

This would be like building from the inside out, and you could even place sound absorbing materials (i.e. foam etc.) between the panels. Of course then we're getting into a lot more building than I want to do - the reason I'm interested in a pre-built box in the first place - but it's an interesting idea...

I thought bracing is used to push cabinet resonances above and outside the bandwidth the cabinet will be playing, while sand and other deadeners attempt to push the resonance below the normal frequency of the cabinet.

I may be completely wrong in my understanding, but now is as good a time as ever to explore.